Psychology 1000 Lecture Notes - Lecture 2: Subliminal Stimuli, Psychophysics, Psychophysiology

• School: Western University
• Department: Psychology
• Course: Psychology 1000
• Professor: Dr.Mike

Document Summary

Sensation: how do we perceive the world around us, psychophysics and psychophysiology, psychophysics. Relation between physical stimulus and physical response. Can determine a just noticeable difference (jnd: threshold. Value of a stimulus characteristic required to produce some response. Difference threshold: amount of change for jnd. Weber"s law: size of difference threshold relative to physical intensity of test is constant, can predict other jnd"s, can compare the sensitivity of different systems. 1: value of jnd is not constant, the relative difference is constant, weber constants: Steven"s power law (best law: more predictive across a variety of sensations, fechners law: s = k log l, stevens: s = k log i^n. 2. is our behaviour affected by subliminal stimuli below threshold: james vicary (1957) Claimed 50% increase in popcorn sales after a 30 second subliminal message in a movie. Concern about the use of subliminal cuts . Turns out he lied about all the data and it was not true: william tapley.